4种杀虫剂对南亚实蝇各虫态不同日龄的毒力测定

Toxicity of four types insecticides to different stages and ages of Bactrocera tau

为明确南亚实蝇Bactrocera tau Walker不同发育阶段、不同日龄以及不同性别成虫对常用杀虫剂的敏感度,本研究采用胃毒法测定了杀虫剂对南亚实蝇室内种群幼虫和成虫的活性,采用浸泡法测了杀虫剂对卵和蛹的活性。结果表明4种杀虫剂对南亚实蝇不同日龄各虫态的毒杀活性存在差异,随日龄增加,各虫态对不同药剂的耐药性增加,且耐药性的强弱不同。高效氟氯氰菊酯EC对南亚实蝇卵、2日龄和5日龄幼虫具有较好的毒杀活性,LC_(50)分别为2.88 mg/L、2.08 mg/L和6.39 mg/L,辛硫磷EC、多杀霉素SC以及高效氯氰菊酯EC的杀虫活性较差,LC_(50)分别为4.71 mg/L、3.95 mg/L和11.60 mg/L;幼虫对高效氟氯氰菊酯EC的耐药性增长较快,对多杀霉素SC的耐药性增加较慢;多杀霉素SC对2日龄和5日龄的蛹和雌雄成虫的毒杀活性较高,但耐药性增加较快,蛹对辛硫磷EC的耐药性增长较慢,雌雄成虫均对高效氯氰菊酯EC耐药性增长较慢,不同日龄的雌成虫的耐药性均高于雄成虫。由于南亚实蝇世代重叠严重,在成虫暴发期之前,可将高效氟氯氰菊酯EC作为首选药剂使用,在成虫暴发期之后防治时可将多杀霉素SC作为优选药剂使用,防治最佳时期为各虫态的初期。

This study aims to clarify the susceptibility changes of Bactrocera tau to insecticides at different developmental stages,ages and sexes.In the study,the toxicity of the larvae and adults of the indoor population were measured by stomach toxicity method,and the toxicity of the eggs and pupae of the indoor population were measured by soaking toxicity method.The results showed that the toxicity of four types of insecticides against B.tau were different at different ages.With the increase of age,the resistance of each stages increased,and the strength of resistance was different.The results showed that Beta-cyfluthrin EC had the best insecticidal activity to eggs,2-day-old and 5-day-old larvae of the B.tau,with LC_(50) of 2.88 mg/L,2.08 mg/L and 6.39 mg/L,respectively.The insecticidal activities of Phoxim EC,Spinosad SC and Beta-cypermethrin EC were 4.71 mg/L,3.95 mg/L and 11.60 mg/L,respectively.The results showed that insecticidal activity of Spinosad SC to 2-day-old pupa and 5-day-old pupa and male and female adults were higher,but resistance increased rapidly.The resistance of pupae to Phoxim EC increased slowly.The resistance of female adults to Beta-cypermethrin EC increased slowly.The resistance of female adults at different ages was higher than that of male adults.Due to the serious overlapping of generations of B.tau,Beta-cyfluthrin EC was used as the preferred insecticide before the adult outbreak period,and Spinosad SC could be used as the preferred insecticide after the adult outbreak period,and the best control period was the younger age of each developmental stages.